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  1. Astra's Chris Kemp asserts RL won't be competitive with SpaceX at 8t for $50m-$55m. RL's Peter Beck corrects that actually is 13t disposable. So the article states materials for Neutron at $20m-$25m. At 50% margin that'd sell for maybe as little as $30m for 13t, or $2.3k/kg. SpaceX can do 23t for $15m-$30m internally, so maybe selling for as much as $45m with a 50% margin. That's $2.0k/kg. At the opposite extreme, F9 may be able to manage $1k/kg with a 50% margin whilst Neutron could be at $2.9k/kg. So it looks like Neutron will probably be between 115% (best case) to 290% (worst case) as expensive as F9 for 3rd party megaconstellations, which will be the main external customers for launches going forward. Chris Kemp is entirely correct that RL needs to do better.
  2. Also, "unused capacity" is irrelevant, all other things being equal. It may actually be preferable, because a rocket flying comfortably under its capacity will be able to accomplish its mission after an engine-out, and/or fly a less efficient but more payload friendly trajectory. A rocket flying right at its limit has no contingency.
  3. Falcon 9's internal marginal cost at last given numbers was somewhere between $15m for RTLS or expended at end of life and $30m for an all new vehicle expanded on first flight. F9's disposable upper stage is bigger than Neutron's, and F9 doesn't have perfect reuse on fairings. It's certainly feasible that Neutron has a path to being cheaper than F9. That's why it's disappointing that it's not. There's a crowd of competitors all coming out with their own next gen vehicles, and only Relativity seems to be aiming beyond F9. ULA Vulcan will probably do ok due to DoD and "anyone but SpaceX" Kuiper contracts, but in the long run even they will need to go back to the drawing board. If Neutron had been able to undercut F9 with a similar cost per kg (which is the metric for megaconstellations that Peter Beck explicitly wants in on), then Neutron could have been a genuine contender. If this sounds like I'm being negative about RL then I'm sorry - I genuinely want someone to get into a serious price war with SpaceX but it doesn't sound like Neutron's going to be well positioned for that anymore.
  4. Same price, half as capable, over half a decade later to market. It's honestly a little disappointing.
  5. Fission can just be turned on and off. ~6% operating thermal power comes from fission product decay though, reducing to about 0.1% over ~40 days, so. You don't necessarily have to provide cooling for decay heat if you don't care about the state of the engine after it's finished firing (propellant exhausted, non-earth intersecting stage trajectory, doesn't matter if it melts.) Fission fragment engines avoid this altogether by exhausting the fuel, so the engine isn't going to get hot from spent fuel emitting decay heat inside the engine But there's no reason not to tap some heat off the power cycle (or decay heat cooling) for electricity generation if you don't mind bringing a little extra mass along.
  6. V2 minis (F9 compatible), not V2 (Starship only) Not heard anything new on that beyond the tweet I think you're referring to.
  7. Tory Bruno gets a big pass for being a thoroughly nice guy. But it's a very pro-what-ULA-developed slant on the whole process for obvious reasons. I agree entirely with this Twitter thread rebuttal:
  8. Duna Mission, had a Mk1-3 gumball with a large lander in an XL large cargo bay. Arrived at Duna, and and launched the lander by opening the cargo bay and decoupling by a large decoupler. The camera and navball stayed fixed to the original craft, but the control inputs were affecting the lander. (Impossible to pilot lander). Kerbal manager/resource manager/tracking station still treated the ship as one unit despite it being in different physics bits and drifting in multiple directions. Unable to swap between control of craft.
  9. "no crasher stages" is a particular issue for disposal of earth departure stages. Those come in especially hot & heavy.
  10. This "reveal" seems like a load of nothing to me, given that they're using a cover layer on the space suit to conceal the actual details.
  11. I still don't understand why "don't build a noodle" is something you have to teach. There's no good reason for long rockets not to be a valid design. You shouldn't have to strut side boosters up like a Christmas tree just so the wibbling thrust vectors don't cause the rocket to flip despite appropriate CoM/CoA positions. These are all artificial workarounds that fail to address the root flaw: unstable rockets are frustrating, creatively limiting, and unfun.
  12. This couldn't be stupider if they tried: STS is already the system name for the space shuttle, so this is just going to cause confusion. The whole Artemis/Orion/SLS naming has been a bin fire from the start.
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